1. Field of the Invention
This invention relates to a cable guard for a compound bow. More specifically, a cable guard that reduces the noise generated by the vibration of the cables, and at the same time, helps increase the speed of the arrow.
2. Description of the Related Art
In the sport of archery, the basic configuration and operation of compound bows are generally known as they have been in use for a long time. Compound bows are used a great deal in hunting, because they provide several distinct advantages. Compound bows mechanically reduce the maximum draw weight, allowing the archer to hold full draw at a draw weight less than that of the required maximum.
Compound bows also achieve more gradual arrow acceleration upon release with reduced stress on the arrow and the archer, which increases the arrow speed and shooting accuracy.
Compound archery bows include tension cables and a bowstring, which are connected between the upper and lower bow limbs. It is customary, in order to minimize any twisting torque on the bow limbs, to dispose the bowstring and the tension cables relatively close together, proximate the vertical centerline of the bow.
A problem presented by compound bows is that a noise is generated upon releasing the bowstring to propel the arrow. When the bowstring reaches the end of its arrow-propelling path, the cables which cross in the center portion of the bow rub against each, causing frictional forces that produce cable wear and create a noise or sound which may alert game birds and animals.
A popular solution to this problem is to provide compound bows with a cable guard having a rod mount which, by rotation of the mount, provides a selectable degree of displacement of the tension cable from the plane of the path of the bowstring. The rod mount is generally threaded directly into the bow handle area, either above or below the handgrip.
The prior art shows that numerous attempts have been made to maintain the lateral spacing of the cables and reduce the friction between the cables.
U.S. Pat. No. 4,452,222 entitled xe2x80x9cCable Guard for a Compound Bowxe2x80x9d to Quartino et al. discloses a cable guard, which comprises a rod that extends from the bow handle and beyond the cables when the bow is in a fully drawn position. The rod is positioned laterally from the bowstring to void any interference with the bowstring. A cable-retaining member is rotatably and slidably mounted on the rod. The cable-retaining member includes two bores that are perpendicular to the rod for slidably receiving the cables to hold them in a lateral spaced relationship with the bowstring.
U.S. Pat. No. 4,596,228 entitled xe2x80x9cCable Separator for Compound Bowsxe2x80x9d to Smith discloses a rod attached to the handle portion of the bow that extends rearwardly beyond the bowstring. Positioned about the external surface of the rod is a cable guard assembly which positions a cable on either side of the bow. The purpose of the invention is to prevent an interfering contact of the cable strands with an arrow during impelling flight of the arrow from the bow, thereby obviating impairment of the true flight of the arrow released from the bow.
U.S. Pat. No. 5,718,213, entitled xe2x80x9cSwing Arm Cable Guardxe2x80x9d to Gallops Jr. et al., discloses a cable guard, including a support member and a swing arm pivotally connected thereto. A cable retaining means having two bores therein for retaining the cables is pivotally mounted on the swing arm. The angle between the support member and the swing arm is such that when the bow is drawn, the distance between the cables, which is contained in the cable retaining means, and the plane of the bowstring travel, is less than the distance between the cables and the plane of bowstring travel when the bow is at rest. Since the cables are closer to the plane of bowstring travel when the bow is drawn, the cables and bow limbs are less stressed when the bow is drawn. The cable guard retaining means may not be adjusted to change the distance between the cable guard retaining means and bowstring.
In prior art, cable guards of the type described above, the rod on which the retaining members were slidably mounted, was required to be of sufficient length to permit the retaining members to be mounted thereon when the bow was in the drawn condition.
Unfortunately, the rod length can be a potential distraction to the archer when the arrow is being shot. Another problem presented by the rod of the prior art is that most archers do not remove the cable guard from their bow for transport, and since many forms of transportation require bows to be cased for transport, the use of such cable guards requires substantial storage area and larger bow cases.
Further, the rod and sliding retainer introduces additional friction into the system, for example, the increased friction force between the cables and the sliding retainer and between the sliding retainer and the support rod as the bowstring is moved from brace position to full draw.
Some of these disadvantages appear to have been overcome by the cable guard disclosed in U.S. Pat. No. 4,834,061 entitled xe2x80x9cCable Vibraguardxe2x80x9d to the present inventor, in which a support member has a swing arm pivotally attached thereto. A cable retaining member having two openings therein is located at the free end of the swing arm. The cables pass through and are contained within the openings of the retaining member. When the bow is drawn, the cables travel in a plane parallel to the general direction of the bowstring and cause the retaining member and connected swing arm to be pivoted away from the support member and the bow handle. The present invention is an improvement of the cable guard disclosed in this patent.
The present invention concerns another means for reducing the frictional forces between the cables and the bores of the retaining means.
Another problem presented by a conventional compound bow is that a considerable amount of energy stored in bow limb is wasted by propelling the bow limb forward when the drawn bowstring is released. Instead, it is desirable to use at least a portion of this wasted energy to propel an arrow.
The arrow speed depends upon several factors, one of the most important being the amount of energy put into the bow. Generally speaking, the more total energy put into the bow, the faster that the arrow will be propelled. Increased arrow speed is desirable, especially when hunting and shooting heavy arrows.
Another problem presented by a conventional compound bow is that the crossing cables are located in the point of view of the archer, thus the visibility of the archer is diminished.
Thus, the present inventor feels the necessity of providing a cable guard for a compound bow that is simple, quiet, inexpensive, and less susceptible to wear and tear, increases the visibility of the archer, and, at the same time, increases the arrow speed.
Therefore, it is an object of this invention to provide a cable guard that separates the cable positioned between the bowstring and the handle portion of a compound bow.
It is yet another object of the present invention to provide a cable guard that decreases the noise generated during the use as to not alert or frighten game birds and animals.
It is yet another object of the present invention to provide cable guard in which the frictional forces generated between the cables and the cable retaining members are reduced when the bow is drawn.
It is yet another object of the present invention to provide a cable guard which does not extend beyond the cables positioned between the bowstring and the handle portion of the compound bow.
It is yet another object of the present invention to provide cable guard with reduced hand shock and vibration in order to avoid arm fatigue.
It is yet another object of the present invention to provide a cable guard which is economical to produce and maintain.
It is yet another object of the present invention to provide a cable guard that separates the cable positioned between the bowstring and the handle portion of a compound bow increasing the visibility of the archer.
It is yet another object of the present invention to provide a cable guard that helps increase the speed of the arrow.
In view of the foregoing disadvantages inherent in the known types of security systems in the prior art, the present inventor discovered a unique cable guard for use with a compound bow, the compound bow having a handle portion and a pair of opposite bow limbs, a first and a second cable which cross one another in extending between opposite bow limbs and a bowstring, the cable guard comprising:
a rod having a first end and a second end, wherein the first end of the rod is attach to the handle portion of the compound bow;
a housing disposed at the second end of the rod;
a pair of swing arms extending opposite to each other and outwardly from the housing in the direction of the bow limbs, the pair of swing arms pivotally connected about a point near one end of the housing;
a biasing means in contact with the other end of the housing and the second end of the rod; and
wherein when the bowstring is drawn to a draw position, the swing arms move in the direction of the bowstring moving the housing in the direction of the handle compressing the biasing means.
The cable guard further can include mounting means for attaching the first end of the rod to the handle portion of the compound bow; a biasing housing located near the second end of the housing, wherein the biasing housing comprises a center axis, wherein the second end of the rod runs through the center axis of the biasing housing; a pair of levers means, wherein each levers means is pivotally connected between the pivot point of the swing arm and the second end of the housing; and a cable guide means positioned at the first end of each swing arm, the cable guide means adapted slidably receiving and separating the first and second cable;
When the bowstring is drawn to a draw position, the cables move in the direction of the bowstring urging the swing arms in the direction of the bowstring. The movement of the swing arms moves the pair of lever means, and the movement the pair of lever means urges the biasing housing in the direction of the handle compressing the biasing means inside the biasing housing.
When the bowstring is release, the biasing housing moves back to it original position and the first and second cables are compelled to stop vibrating by the movement of the biasing housing returning to the original position thereby decreasing the amount of vibration noise produced by the vibrating of the first and the second cable.
The biasing housing includes a first portion and a second portion, wherein the diameter of the first portion is greater than the diameter of the second portion forming a seat.
The compression of the biasing means adds an extra tension force to the biasing means, and wherein the extra tension force provides the arrow with an increase speed.
In a first preferred embodiment, the biasing means comprises more than one spring.
Further, the present invention contemplates the use of an adjusting rod to engage the biasing means and change the pre-set compression force of the biasing means.
The foregoing has outlined rather broadly the more pertinent and important features of the present invention in order that the detailed description of the invention that follows may be better understood, and the present contribution to the art can be more fully appreciated. Additional features of the invention will be described hereinafter, which form the subject of the claims of the invention. It should be appreciated by those skilled in the art that the conception and the specific embodiments disclosed may be readily utilized as a basis for modifying other security systems for carrying out the same purposes of the present invention. It should also be realized by those skilled in the art that such equivalent structures do not depart from the spirit and scope of the invention as set forth in the appended claims.